Figure 1.
Chemical structures of nucleoside antibiotics in this study: dealanylascamycin 1, ascamycin 2, nucleocidin 3.
Figure 2.
Gene organization of ascamycin/dealanylascamycin biosynthesis pathway.
A) AcmA to AcmW. B) Chlorinases acmX and acmY.
Table 1.
Deduced ORFs and their predicted functions in the ascamycin/dealanylascamycin gene cluster.
Figure 3.
Proposed model for Acm/Dacm and 5′-O-sulfonamide group biosynthesis.
A) Biosynthetic pathway of ascamycin/dealanylascamycin. B) Biosynthetic pathway for 5′-O-sulfonamide group formation.
Figure 4.
Analysis of metabolite profiles of Streptomyces JCM9888 and related mutants.
A) HPLC-UV analysis of metabolite profiles of Streptomyces: i) Wild type JCM9888, ii) ΔacmG mutant, iii) ΔacmK mutant, iv) ΔacmE mutant. The products DACM (1), ACM (2) are indicated. B) HPLC-ESI-MS analysis of metabolite profile of JCM9888 under the same program of HPLC-UV. C) The molecular formula of compounds DACM (1), ACM (2) were determined to be C10H13ClN6O6S (m/z = 381.0384, 383.0354 [M+H]+) and C13H18ClN7O7S (m/z = 452.0755, 454.0725 [M+H]+) on the basis of ESI-HRMS. D) MS/MS pattern of ascamycin and dealanylascamycin are shown and the detected data is closely consistent with anticipated fragmentation ions. D1: dealanylascamycin; D2: ascamycin.